Killing members of the Cult of Kosmos will land you Legendary Gear and shards of the Spear. Upgrading your spear to level 5 unlocks more Abilities. Here's every location of every Cult Member and how to kill them.

These are tablets (documents) you'll find in different locations around Greece. The riddles the tell will lead you to treasure and special Engravings for your Weapons and Armor if solved. See our Ainigmata Ostraka Locations to find the tablets and their solutions.

Assassin's Creed Odyssey has plenty of references around the world. See our Easter Eggs and References page to see Easter Eggs from Zelda, Black Panther, and more. Here's a Zelda reference, for example: